Validity for what? What is your question/task/purpose?

TLDR: BPC is great for displaying/highlighting un-known/higher intensity peaks in a busy chromatogram....if you know the peaks, do a select ion chromatogram to highlight...if you are trying to find out what is there that you didnt know before...use an automated feature detection/identification routine like AMDIS/NIST library matching.

the long...

Base peak chromatograms simply take the intensity of the most intense ion of each spectra at each point in the chromatogram and report that as the Y axis of the chromatogram. By definition the 'base peak' (mass spectral peak not chromatographic) is more strongly correlated with a given molecule's chromatographic profile and less likely to get 'lost' in the sea of total ion signal...hence to the human eye the BPC looks less 'noisy' (easier to see/comprehend a couple prominant chromatographic peaks). Multiple studies show a vast majority of GC-MS 'noise' is chemical 'noise' (ie unanticipated, not explicitly/easily identified but totatlly logical molecules eluting from the system and producing corresponding ion signal which we dont always readily identify, sometimes chromatographically resolved (fingerprints, septum bleed etc), sometimes not (ie column bleed, highly polar compounds etc).

Since (I presume) you are performing GC-EI-MS, fragmentation is heavy and fairly compound specific. Therefore the BPC peak heights will be more dependant on the combination of a given compound's concentration AND its structure's propensity to fragment into many ions (symetric repetitive structures= many equal intensity fragments, less BPC height; asymetric or weak-link structures a few higher intesity fragments, more BPC height); whereas a TIC peak intensity will be more a function of concentration and effective carbon number (ie total ions produced, fragments or not).

Since BPCs are just a way to visualize a small portion of a much larger data set, any routine analytical method using modern GC-MS software will not rely on the BPC but rather use the whole data set (full spectra...or target ions etc). Hence I am not sure what you mean by 'valid'.

Dr. Aravinna is wrong. BPC allows you to separate signal from noise for select compound classes, especially those that do not fragment heavily (like polynuclear aromatics). It is simply another way to look at your data, and overlaid with TIC it shows you degree of fragmentation on a whole chromatogram basis. In MS you almost never use TIC for quantification as most methods are written around extracted ions (prominent or characteristic ions).

I have removed my answer.

thank you for the comment.

there is a mistake in the answer.